2011 Arctic Cat 366SE ATV Service Manual, Page 39Get this manual
12With the alignment pin installed in the camshaft and the cam lobes directed down (toward the piston), place the camshaft in position and verify that the timing mark on the magneto is visible through the inspection plug and that the timing marks on the camshaft sprocket are parallel with the valve cover mating surfaceNOTE: When the camshaft assembly is seated, make sure the alignment pin in the camshaft aligns with the smallest hole in the sprocket BCamshaft lobes directed down (toward the piston)CCamshaft alignment marks parallel to the valve cover mating surfaceDRecessed side of the sprocket directed toward the cam lobesECamshaft alignment pin and sprocket alignment hole (smallest) are aligned
13With the alignment pin installed in the camshaft, loosely place the cam sprocket (with the recessed side facing the camshaft lobes) onto the camshaft and place it into position with the cam chain over the sprocket
CAUTION
If any of the above factors are not as stated, go back to step 13 and carefully proceed
16Place the tab washer onto the sprocket making sure it covers the pin in the alignment hole